Problem: $ { {4} \times \left[\begin{array}{r}{-2} \\ {-2} \\ {2}\end{array}\right] = {?} } $
Answer: To multiply a matrix by a number, multiply each item of the matrix by the number. ${\left[\begin{array}{r}{4}\times{-2} \\ {4}\times{-2} \\ {4}\times{2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{r}{-8} \\ {-8} \\ {8}\end{array}\right]}$